MTG16 is a member of the Myeloid Translocation Gene (MTG) family of proteins. The genes that encode MTG proteins are preferred targets of frequently observed proleukemic chromosomal translocations. Evidence also ascribes a tumor suppressor role to members of the MTG family. MTG proteins function as transcriptional corepressors, coordinating interactions between histone deacetylases, corepressor proteins and site specific DMA binding proteins, including T-cell factor (TCP), at target promoters. How MTG 16 is regulated is not known, and is the focus of this proposal. To explore MTG16 regulation, its phosphorylation will be studied. The effect of observed phosphorylation events on MTG 16 transcriptional corepressor function will be explored and correlated with corepressor complex composition and integrity. Experiments directed toward identification of the responsible kinases will be conducted. Ultimately, the goal is to ascertain the effect of specific phosphorylation events on growth, transformation and development. These data may have future therapeutic implications for diverse cancer types.